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An approximate two-dimensional Green's function for an electrically thick and large dielectric slab is presented. In doing so, we first obtain the interior Green's function which solves the case when the source and field points are inside the dielectric slab. For the cases when the source and/or field points are outside the slab, the Green's function is obtained using the interior Green's function and the surface equivalence principle. According to the surface equivalence principle, having the interior Green's function is adequate to find the solution for the arbitrary source and field point positions. The solutions for all possible cases are obtained numerically and are validated by comparing to the results generated by the surface integral equation/method of moments. (6 pages)

The interactions of hadron spin with gravity and electromagnetic field and their implication for hadron spin structure are considered. The extension of equivalence principle naturally leads to the closeness of vector meson magnetic moment to that of electroweak boson. This similarity is confirmed in the lattice QCD. The effective gravity in AdS/QCD allows to connect the [Formula: see text]-dependence of GPDs (and therefore electromagnetic and gravitational form factors) with [Formula: see text]-dependemce of TMDs. The possible cosmological implications of equivalence principle extension are discussed.

I will discuss three related unconventional ways to generate neutrino oscillations (1)Equivalence principle violation by the string dilaton field (i2)Violation of Lorentz Invariance and (3) Equivalence principle violation through a non-universal tensor neutrino-gravity coupling. These unorthodox neutrino oscillation mechanisms are shown to be viable at the level of our present experimental knowledge and demonstrate that neutrino oscillations can probe very profound questions.

The manifestation of equivalence principle (EP) in spin-gravity interactions, resulting in the nullification of the corresponding analog of Anomalous Magnetic moment is explored. Its tests in the experiments with atoms and cold neutrons are discussed. The validity of EP separately for quarks and gluons in the nucleon resulting in exact equipartition of momentum and total angular momentum is conjectured. The important role of relocalization (Belinfante) invariance in these and other aspects of nucleon spin structure is stressed., 4 pages, contribution to SPIN 2006, Kyoto, October 2-7

The Newtonian approximation for the gravitational field equation should not necessarily involve admission of non-relativistic properties of the source terms in Einstein's equations: it is sufficient to merely consider the weak-field condition for gravitational field. When a source has electromagnetic nature, one simply {\em cannot} ignore its intrinsically relativistic properties, since there cannot be invented any non-relativistic approximation which would describe electromagnetic stress-energy tensor adequately, even at large distances where the fields become naturally weak. But the test particle on which gravitational field is acting, should be treated as non-relativistic (this premise is required for introduction of the Newtonian potential $\Phi_{\rm N}$ from the geodesic equation)., Comment: 5 pages, a talk delivered at the 11th Marcel Grossmann Meeting (Session GT4), Berlin, 2006

A equivalence principle algorithm using the method moments is introduced. Complex structures can be decomposed into smaller, simpler structures using simpler equivalence surface which will help the electromagnetic modeling of complex structures in electrical packages.

A scheme is presented to apply multilevel fast multipole algorithm (MLFMA) to analyze the scattering and radiation for three dimensional (3D) objects comprising conducting and dielectric bodies. Applying equivalence principle, PMCHW formulations are used on the surface of the 3D dielectric bodies and EFIE is used on conducting surface. The far-field matrix-vector multiplication and the near-singular problems are analyzed. Application of MLFMA reduces the memory requirement and computational complexity of the MOM solution significantly, which renders us to analyze the electrically large objects. Numerical examples are presented to demonstrate the accuracy and high efficiency.

We study the possibility of experimental testing the manifestations of equivalence principle in spin-gravity interactions. We reconsider the earlier experimental data and get the first experimental bound on anomalous gravitomagnetic moment. The spin coupling to the Earth's rotation may also be explored at the extensions of neutron EDM and g-2 experiments. The spin coupling to the terrestrial gravity produces a considerable effect which may be discovered at the planned deuteron EDM experiment. The Earth's rotation should also be taken into account in optical experiments on a search for axionlike particles., Comment: 12 pages, version to appear in Physical Review D

We discuss two effects predicted by the general theory of relativity in the context of Rindler accelerated observers: the gravitational spectral shift and the time delay of light. We show that these effects also appear in a Rindler frame in the absence of gravitational field, in accordance with the Einstein's equivalence principle., Comment: 12 pages, 3 figures

The non-abelian Einstein-Born-Infeld-Dilaton theory, which rules the dynamics of tensor-scalar gravitation coupled to a $su(2)$-valued gauge field ruled by Born-Infeld lagrangian, is studied in a cosmological framework. The microscopic energy exchange between the gauge field and the dilaton which results from a non-universality of the coupling to gravity modifies the usual behaviour of tensor-scalar theories coupled to matter fluids. General cosmological evolutions are derived for different couplings to gravitation and a comparison to universal coupling is highlighted. Evidences of cosmic acceleration are presented when the evolution is interpreted in the Jordan physical frame of a matter respecting the weak equivalence principle. The importance for the mechanism of cosmic acceleration of the dynamics of the Born-Infeld gauge field, the attraction role of the matter fluid and the non-universality of the gravitational couplings is briefly outlined., 31 pages, 9 figures, minor changes, accepted for publication in Phys. Rev. D15

It is shown that the gravitational ultrarelativistic spin-orbit interaction violates the weak equivalence principle in the traditional sense. This fact is a direct consequence of the Mathisson-Papapetrou equations in the frame of reference comoving with a spinning test particle. The widely held assumption that the deviation of a spinning test body from a geodesic trajectory is caused by tidal forces is not correct, 12 pages

On incorporating special relativity theory into an extended equivalence principle, post-Newtonian gravitational phenomena beyond that originally predicted by Einstein are predicted (required), such as geodetic and gravitomagnetic precessions of local inertial frames, and precession of Mercury's orbital perihelion. Why were not these phenomena predicted in the years 1907-1911? The unique 1/c^2 order dynamical equations for clock rates and motion of both bodies and light in local gravity are derived which guarantee fulfillment of the special relativistic equivalence principle.

In this paper, a computationally efficient approach using equivalence principle for the method of moments solution of the infinite doubly periodic frequency selective surfaces has been introduced. This approach involves forming a dual screen geometry with reduced metallization, which in turn leads to a reduction in the number of unknowns. Reformulation of the problem by using MFIE is not necessary, and the existing legacy codes employing the EFIE can easily be modified to accommodate the present approach. Numerical experiments reveal the accuracy and the computational advantage of this technique when compared to the conventional techniques.

The generalized Stokes theorem (connecting integrals of dimensions 3 and 4) is formulated in a curved space-time in terms of paths in Minkowski space (forming Path Group). A covariant integral form of the conservation law for the energy-momentum of matter is then derived in General Relativity. It extends Einstein's equivalence principle on the energy conservation, since it formulates the conservation law for the energy-momentum of matter without explicit including the gravitational field in the formulation., Comment: 9 pages, Latex, one figure

The recent measurements of the absolute value of the Newtonian gravitational constant, G, are discussed and some thoughts on the direction of future work in this area are presented. Although some of the recent searches for variations in G are also mentioned, special attention is paid to one branch of that work focusing on the possibility of detecting variations in G with temperature. Past experimental searches for such an effect are reviewed.

A novel idea, termed as uncertainty equivalence principle, is proposed, based on which an equivalent measure to the H/sub /spl infin//-norm is adopted for unmodeled dynamics using time-domain measurement data. Such an equivalent description for modeling errors is consistent with H/sub /spl infin//-based robust control, and allows H/sub /spl infin// optimization to be successfully used in adaptive control to achieve robust stability and performance comparable to H/sub /spl infin// control. Specifically a new adaptive control systems is proposed in this paper, focusing on stable plants. It employs the recursive least-squares (RLS) algorithm for adaptive model estimation, and weighted sensitivity minimization plus robust stabilization for adaptive controller design. Our results show that the proposed adaptive control system admits robust stability and performance asymptotically, provided that the estimated plant model converges.

Presents an inertia equivalence principle that exposes the relation between the dynamics of a parallel manipulator, and that of its arbitrary reduced tree systems. This principle, along with the D'Alembert principle, leads to a precise proof of the nontrivial fact that the virtual work principle is also valid for the two different physical systems, a parallel manipulator and its reduced tree system, under a given condition. The dynamics of parallel manipulators and its properties are then given. Two control algorithms are then provided. Firstly, we implement a geometric control algorithm that is based on the Riemannian metric structure associated with the kinetic energy of the manipulator. Motivated by this, an adaptive control algorithm is then proposed in which only dynamic parameters are required to be updated. Geometric reinterpretation of this algorithm as the passive port controlled system is given. Its asymptotic stability is therefore obvious. The new content of this algorithm compared with the traditional ones is discussed. Experimental results are reported that demonstrate the effectiveness of the algorithms.

I briefly present the Organizing Committee’s and my own motivation for organizing this workshop, and I suggest a few key questions for which we will try to find possible answers in the coming days.

The concept of the modified equivalent surface current is introduced for an electromagnetic field in a homogeneous and biisotropic region. © 1994 John Wiley & Sons, Inc.

The application of integral equations to the analysis of thinly coated perfect electric conductors, in particular coated reflector antennas, is examined with emphasis upon the controllability of the far-field radiation patterns. A set of coupled-field integral equations, derived from enforcing boundary conditions and equivalence principle, represents the fields exterior and interior to the coating region and accounts for all of the scattering mechanisms associated with the problem. Results using integral equation techniques are presented which demonstrate the effectiveness that rim loading has in the control of the far-field patterns. >

The SEMN method was previously introduced by Tavakkol-Hamedani and Tavakoli (see IEEE AP-S Symposium, p.2358-61, 1997) and general formulas and derivations for the analysis of complex structures were presented. In order to eliminate singularities in the source region, closed-form expressions for computation of the self-coupling matrices of rectangular and circular segments with uniform equivalent electric and magnetic surface currents are derived. We also analyzed a finite microstrip antenna and obtained good agreement between the theoretical and experimental results.

A new method for the analysis of arbitrary shaped multilayered printed antennas is presented. It is also applicable to numerous other radiation and scattering problems. Admittance matrices of the differential surface elements of homogeneous and isotropic sections are computed using the surface equivalence principle and Green's functions of homogeneous space. Then, using multiple network theory, the overall characteristic of the composite antenna is derived. In this method, we do not need the Green's functions of composite materials and the calculation of Sommerfeld-type integrals. Additionally, all the field parameters are represented in terms of surface parameters, and the singularity of the source elements is analytically removed.

Alternative predictions developed by Collin, based on Bethe's theory, and Elliott, based on Schelkunoff's equivalence principle and the method of images, for the scattering from a small hole in the broad wall of a piggyback waveguide are described. Experimental data is given that verifies Collin's predictions from Bethe's theory. An apparent conflict between the two formulations is resolved by data generated by two programs that employ the method of moments technique.

The convergence of SEMN (surface equivalence principle and multiple network theory) method in the computation of the input impedance of a probe-fed finite rectangular microstrip patch antenna is studied. Comparing the electric and magnetic field integral equation (EFIE and MFIE) formulations of the SEMN method, it is shown that the MFIE formulation has a better convergence criterion. Also, it is shown that lower size segments are required when the substrate or ground plane are extended beyond the patch.

I explain the geometric basis for the recently-discovered nonholonomic mapping principle which permits deriving laws of nature in spacetimes with curvature and torsion from those in flat spacetime, thus replacing and extending Einstein's equivalence principle. As an important consequence, it yields a new action principle for determining the equation of motion of a free spinless point particle in such spacetimes. Surprisingly, this equation contains a torsion force, although the action involves only the metric. This force makes trajectories autoparallel rather than geodesic. Its geometric origin is the closure failure of parallelograms in the presence of torsion, A simple generalization of the mapping principle transforms path integrals from flat spacetimes to those with curvature and torsion, thus playing the role of a quantum equivalence principle, applicable at present only to spaces with gradient torsion., Comment: Author Information under http://www.physik.fu-berlin.de/~kleinert/institution.html . Paper also at http://www.physik.fu-berlin.de/~kleinert/258

This chapter discusses damage mechanics modeling of fatigue crack growth followed by its validity, and constitutive relations, governing equation of process zone. Damage mechanics modeling of fatigue crack growth is valid when the crack length increment during one load cycle is very small in comparison with the total crack length. The damage coupled constitutive relations of cyclic loading can be established by means of the strain equivalence principle and the Osgood-Ramberg equation and Masing principle in the vicinity of the fatigue crack tip. Further, boundary conditions of the process zone and crack growth rate is discussed.

In a previous paper [gr-qc/0104001; Class. Quant. Grav. 18 (2001) 3595-3610] we have shown that the occurrence of curved spacetime ``effective Lorentzian geometries'' is a generic result of linearizing an arbitrary classical field theory around some non-trivial background configuration. This observation explains the ubiquitous nature of the ``analog models'' for general relativity that have recently been developed based on condensed matter physics. In the simple (single scalar field) situation analyzed in our previous paper, there is a single unique effective metric; more complicated situations can lead to bi-metric and multi-metric theories. In the present paper we will investigate the conditions required to keep the situation under control and compatible with experiment -- either by enforcing a unique effective metric (as would be required to be strictly compatible with the Einstein Equivalence Principle), or at the worst by arranging things so that there are multiple metrics that are all ``close'' to each other (in order to be compatible with the {\Eotvos} experiment). The algebraically most general situation leads to a physical model whose mathematical description requires an extension of the usual notion of Finsler geometry to a Lorentzian-signature pseudo-Finsler geometry; while this is possibly of some interest in its own right, this particular case does not seem to be immediately relevant for either particle physics or gravitation. The key result is that wide classes of theories lend themselves to an effective metric description. This observation provides further evidence that the notion of ``analog gravity'' is rather generic., Comment: 18 pages, RevTex4

In this essay it will be shown that Decoherence Model and Einstein Equivalence Principle are conceptually incompatible. In other words, assuming only the validity of the Weak Equivalence Principle the present work concludes that we face two possibilities: (i) if Decoherence Model provides a correct description of nature at quantum level, then there are systems which violate Local Position Invariance, or, (ii) if all the postulates behind Einstein Equivalence Principle are valid, even on quantum realm, then Decoherence Model breaks down in curved spacetimes. Finally, the present results are confronted against Schiff's conjecture., Comment: This essay received an ``honorable mention'' in the 2001 Essay Competition of the Gravity Research Foundation. Accepted in International Journal of Modern Physics D

The idea that the final distribution of the tax burden (economic incidence) does not depend on the initial distribution of tax liabilities (statutory incidence) is referred to as the Liability Side Equivalence principle. This paper tests this principle in the laboratory and findsthat subjects who actually have to pay the tax carry a higher tax burden. It is argued that this violation of Liability Side Equivalence is due to the fact that a change in the distribution of tax liabilities induces a shift in behaviorally relevant social norms. This shift, in turn, affects the impact of the tax. Our results explain some striking empirical observations and have important theoretical and practical implications.

We have updated the analysis for the solution to the solar neutrino problem by the long-wavelength neutrino oscillations induced by a tiny breakdown of the weak equivalence principle of general relativity, and obtained a very good fit to all the solar neutrino data., 3 pages, 5 figures, uses espcrc2.sty, Talk presented by H. Nunokawa at Europhysics Neutrino Oscillation Workshop (NOW2000), Otranto, Italy, September 9-16, 2000

I contemplate the possibility that the mismatch between the maximally symmetric point (the free fermionic point) and the strictly self-dual point in the Narain moduli space plays a role in the string vacuum selection. The role of self-duality in the recent formulation of quantum mechanics from an equivalence postulate, and the new perspective that it offers on the foundations of quantum gravity and the origin of mass, are discussed., Comment: 8 pages. Standard Latex & sprocl.tex. Invited talk presented at PASCOS 99, Lake Tahoe, CA December 10-16 1999

Using surface equivalence principle and multiple network theory (SEMN) a rigorous method has been introduced for the analysis of finite microstrip antennas [l]. One practical limitation of rigorous methods is that they need extensive CPU time and storage to analyze a finite structure which is not too small electrically. In this article, three symmetry considerations are introduced to reduce the number of unknowns and computations and eliminate this drawback.

We show that the recently formulated Equivalence Principle (EP) implies a basic cocycle condition both in Euclidean and Minkowski spaces, which holds in any dimension. This condition, that in one-dimension is sufficient to fix the Schwarzian equation [6], implies a fundamental higher dimensional Moebius invariance which in turn univocally fixes the quantum version of the Hamilton-Jacobi equation. This holds also in the relativistic case, so that we obtain both the time-dependent Schroedinger equation and the Klein-Gordon equation in any dimension. We then show that the EP implies that masses are related by maps induced by the coordinate transformations connecting different physical systems. Furthermore, we show that the minimal coupling prescription, and therefore gauge invariance, arises quite naturally in implementing the EP. Finally, we show that there is an antisymmetric two-tensor which underlies Quantum Mechanics and sheds new light on the nature of the Quantum Hamilton-Jacobi equation., 1+48 pages, LaTeX. Expanded version, two appendices, several comments, including comparison with Einstein Equivalence Principle, added. Typos corrected, one reference added. To appear in CQG

In this paper, some new techniques for determining the observer-based or LQG form of any compensator with arbitrary order are discussed. The practical appeal of such techniques is that they allow for a simplified implementation and reduced memory storage of general controllers and offer additional flexibility for handling gain-scheduling and input saturation constraints as compensateor states become meaningful variables. The derived observers-based controllers are input-output equivalent to the original controller but with an explicit separated estimation/control structure. Such structures involve both static control and estimation gains with an extra Youla parameter that can be either static or dynamic. The proposed techniques are applicable both in continuous-and discrete-time, to full-order controllers, that is, controllers whose order controllers whose orders are greater or smaller, respectively. Necessary conditions to apply this general controller equivalence principle are derived. The interest and practicality of such techniques are then investigated with regards to the LQG implementation of Hinfinty and u controllers, classes of controllers that does not generally enjoy ease of implementation.

We use measurements of the polarization of light from a magnetic white dwarf to impose sharp constraints on the gravity-induced birefringence of space predicted by a broad class of nonmetric gravitation theories. Since gravity-induced birefringence violates the Einstein equivalence principle, our measurements test this foundation of general relativity and other metric gravitation theories in a new setting.